Everyone has brought up some great points, but I will also add in one other aspect that makes it harder to move industries and that is all the supporting business. There have been many cases where businesses try to move their production to new locations to only discover dependencies that make it nearly impossible. For example, when apple tried to move one of their production lines to the US they discovered that no one locally could manufacture some screws for them in their specific size. Companies were willing to start creating the screws, but it would take a few years to reconfigure their production lines.